This morning I noticed an increase in these egg cases on my glass and I'm curious of what they could be. I estimate there are about 30-40 of these on the front glass at 4 inches or closer to the sandbed. It appears the cases are attached on one end to the glass and there are about 30 or so tiny white eggs inside each. Some possibilities I'm considering: limpets, chitons, sandbed worms, and collonista snails. Anybody have any ideas?